Brake drum construction



May 28, 19 35. c. SINCLAIR 2,003,055

BRAKEDRUM CONSTRUCTION I Filed 'April 18, 1952 2 sheets' shee y 193 5. c. w. SINCLAIR 2,003,055"

I BRAKE DRUM CONSTRUCTION I Filed April 18, 1932 2 Sheets-Sheet 2 I I I 2,oo:,,o55- I I .BRAKE DRUM CONSTRUCTION .7

' acharles W. Sinclair, Detroit, Mich., assignor, by II mesne "assignments, to "The Kelsey-Hayes Wheel Company, Detroit, Mich., a corporation 4 of Delaware g Application April 18, 1932, Serial No. 605,955 I I I 8 Claims. (Cl. 188-218). a V

.- The invention relates to brake drum constructhe back plate and 'forms therewith an eflective tions and has for one. of itsobjectsto provide an seal and furthermore the annular channelpor improvedarrangement of brake drum and back tion of the back plate cooperates with'the liner plate for securing an effectiveseal therebetween. of the brake drum to form an enlarged annular Other objects are to provide an improved arspace forming part of the'seal;

rangement embodying ashield'to protectthe joint The brakej'drum is made by originally formbetween the brake drum and theback plate; to, ing theannular flange 4 withthe inwardly and provide a composite brake drum so constructed rearwardly inclined annular'flangefllconnecting as to secure an improved seal;,and to provide into thereinfor'cing rib'GL inclined flange 10 a construction in which; the retainer f r the extendsasuflicient distanceto forma retainer for 10 brake drum liner also functions as the shield. the molten metal which forms the liner; 5 during These and other objects of the invention will the centrifugal casting of this liner within the become apparent from the following description, brake drum'shell. The casting is earned out at taken in connection with the accompanying temperatures'such as to secure efiectivefusing or drawings, in which I I f 1 I I molecular bonding between the adjacent surfaces 15 Figure l is an elevation of a brake drum conofthe brake drum shell and the liner. After'the struction, showing an embodiment of my invenmolten metal has cooled, the inclined flange l2 tion; a V. 7. and the. adjacent end portion of the liner'are Figure 2 is across section on theline 2-2 of cut away or machined to form the space within Figure .,1'; the annular flange and, more particularly',th'e 20 Figures 3, 4, 5,6, 7, Band Qarevievvs similar reinforcing rib at itsffreeedge to receive the to Figure 2, showing other embodiments of my back plate. The inner face of theline'r is also invention. cutaway or machined and suitably finished to Figures l and 2 show a brake drum construcform the brake engaging surface; I

tion designed particularly for usewith motor ve- V Figure 3 discloses anothermodification in g5v hides and comprisingthe'brakedrum, l ,'which is which the brake drum I3 is formed in substanrevoluble, and the back plate 2 which is 'statially the same manner as thel brak'efdruml, but tionary. The brake drum comprises the sheet the back plate [4 is provided with a 'dirferent metal and preferably sheet steel shell having the peripheral cross section'tha'n' the back plate" 2.

web 3 and the integral peripheral annular flange This back plate I4 has the annular reinforcing 3o 4 and the cast metal. liner 5 within the shell. depression l5 for engaging'and positioning the Thisliner [is preferably centrifugally cast within brake member and-has radially outwardly beyond the shell and is preferablyformed ofcastiron; this annular depression the radially extending The annular flange 4 has at" it's free edge the inportion l6 and the peripheral 'rearwardly extendtegral reinforcing rib 6 and may also have other ing annular flange 11. The reinforcing rib It at as integral reinforcing ribs 1 and 8, if desired. The the free edge of the brake drum shell {substanback plate is preferably formed of sheet metal tially completely encircles"the"annular flange 'or sheet steel and pressed or rolled to shape and I1 andserves in formingan' efiective labyrinth this back plate is formed with the, forwardly oifseal.

40, setannular depression, 9 and the rearwardly off- Figure 4 discloses a modiflcation of Figure 3 40' set channel portion l0',,the latter having its outer in which the back plate .19 is provided with the side wall forming the forwardly extending annular annular series of forwardly extending depressions UNITED S AT S P E T"OFFICE- flange II at the periphery of the back plate. 120 within the liner. of the'compositebrakedrum. The-g annular depression} is located within the," for engaging the brake member. This back plate" liner 5 and is'adapted to engage a brake member," is also provided with the'annular series of op- 45 such as a brake shoe, adapted to cooperate with positely extending depressions 2| which serve the liner. The annular channel portion i0 is with the depression 20 toreinforce the back'plate. located at the end of the liner 5 and is within In the modification disclosed in Figure 5, the and encircled by the reinforcing rib 6, sufiicient, composite brake drum is provided with the clearance being provided between the brake drum flanged ring 22 which serves to retain the molten 50 and more particularly its liner and reinforcing metal during. the centrifugal casting of the liner rib and the back plate to take care of variations 23. This ring is permanently secured, as by weldin manufacture and relative movement of these ing, within the reinforcing rib 24 atthe free edge parts in operation. The arrangement is such of the brake drum shell and has a radially inthat the brake drum extends over and protects wardly extending flange projecting beyond the 2 inner face of the shell to retain the molten metal.

. This flange and the inner face of the liner may the brake member. This annular flange is formed at its free edge with the reinforcing rib 21 which I is adapted to extend axially' ov'er and encircle the back plate 28 including its peripheral rearwardly extending annular flange .28. n =3. is an annular shield of angular cross" section and is resilient and formed of sheet metal. This shield is located within the space between the axially'overlapping portions of the brake. drum and back plate and has the radially extending flange 3| which is suitably permanently secured to the radially outwardly extending portion 32 of the reinforcing .rib 2 1, as by welding. The shield also has the axially extending resilient portion 33 which encircles the annular flange 29 of the back plate and preferably contacts therewith, but exertsbut relatively light pressure thereon.

In the modiflcation shown in Figure 7, the brake drum is a composite brake drum having the shell 34 and-the centrifugally. cast liner 35. The shellhas at its free edge the reinforcing ribli which extends axially over and encircles the back plate 31 with its peripheralrearwardly extending annular flange 38. The annular shield, 38 locatedv in the space between the 'brake'drum shell and, more particularlyits freeedge reinforcing rib, and theback plate and more particularly its peripheral annular flange has the radially extendingflange 40 which is permanently secured as by welding to the reinforcing, rib [36 and which extends radially inwardly beyondthe inner face of theiannula'r flange of the shell to serve as a retainer during the centrifugal casting operation for the molten metal which forms the liner 35. fl'l'hisishieldialso has the axially extending resilient flange which is adapted to extend adjacent to the peripheral annular flange l8 and contact therewith. I L

Figure 8' discloses a modification of Figure, 7, differing mainly in, that the back plate 42' is formed with the forwardly offset annular. depression 43 which reinforces the back plate and is also adapted to engage the brake member within the brake drum. Also in this'modiflcation the annular reinforcing rib 44 at the free edge of the brake drum shell has an inclined side wall 45 and the combined retainer and resilient shield 46 is permanently secured within this rib in a I manner such that the centrifugally cast liner 4! has an annular 'V-shaped portion or rib 48 between theinclined side yalloi thereinforcing rib and the radially extending flange of the combined retainer and shield.

Figure-9 discloses amodiflcation in there is anannular sheet-metal shield 49 located between the brake drum 50 and the back plate II. This shield has an annular or axially extending flange 52 which is seated upon the outer face of the annular depression 53 in theback'plate. The shield is permanently secured to the back plate as by welding and has a radially extending flange which is adapted to extend adjacent to and preferably contact with the radially outwardly extending wall 54 of the reinforcing rib at the free edge of the annular flange of the brake drum shell.

What I claim as my invention is:

1. In a brake drum construction, the combination with a revoluble brake drum and a back plate encircled by said. brake drum, of a shield secured to and revoluble with said brake drum and extending axially between said brake drum and back plate.

2. In a brake drum construction, the combination with a revoluble brake drum and a back plate encircled by said brakedrum, of a shield secured to the brake drum within the latter and revoluble with said brake drum and having an axially extending portion adjacent to said back plate.

.3. In a brake drum construction, the combination with 'a revoluble brake drum and a back plate encircled by and spaced from said brake drum, of a shield secured to and revoluble with said brake drum and extending within the space between saidbrake drum and back plate and'encircling a :portion' of said back plate.

4. In' a brake, drum construction, the combination with a back plate, of a revoluble brake drum comprising an annular flange, a liner within said flange, and a-retainer for said liner permanently secured to said flange and providing a space with in said flange receiving said back'plate. 5. In a brake drum construction, the combination with a back plate, of a revoluble brake drum comprising an annular flange encircling said back plate, a liner within said flange, and a retainer for said liner permanently secured to said flange and forming a shield extending adjacent to said back plate.

6, In a brake drum construction, the combina-' tion with a back plate, of a revoluble brake drum comprising an annular flange encircling said back plate, a liner within saidflange, and a retainer for said liner permanently secured to said flange and having an'axially extendingportion adjacent to said back plate. I

7. In a brake drum construction, the combination 7 with a brake and a back plate encircled by and spaced from said brake drum, of a shield within the'sp'ace between said brake drum and back plate and secured to one of said members and extending adjacent to the other. I

8; In a brake drum construction, the combination with a back plate, of a revoluble brake drum comprising an annular flange, a liner within said flange, and a retainer for the liner permanently secured to the drum and extending adjacent to the back plate to form a shield between the latter and drum. I v 

